1 files changed, 132 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/botocore/retries/adaptive.py b/.venv/lib/python3.12/site-packages/botocore/retries/adaptive.py
new file mode 100644
index 00000000..5e638ddb
--- /dev/null
+++ b/.venv/lib/python3.12/site-packages/botocore/retries/adaptive.py
@@ -0,0 +1,132 @@
+import logging
+import math
+import threading
+
+from botocore.retries import bucket, standard, throttling
+
+logger = logging.getLogger(__name__)
+
+
+def register_retry_handler(client):
+    clock = bucket.Clock()
+    rate_adjustor = throttling.CubicCalculator(
+        starting_max_rate=0, start_time=clock.current_time()
+    )
+    token_bucket = bucket.TokenBucket(max_rate=1, clock=clock)
+    rate_clocker = RateClocker(clock)
+    throttling_detector = standard.ThrottlingErrorDetector(
+        retry_event_adapter=standard.RetryEventAdapter(),
+    )
+    limiter = ClientRateLimiter(
+        rate_adjustor=rate_adjustor,
+        rate_clocker=rate_clocker,
+        token_bucket=token_bucket,
+        throttling_detector=throttling_detector,
+        clock=clock,
+    )
+    client.meta.events.register(
+        'before-send',
+        limiter.on_sending_request,
+    )
+    client.meta.events.register(
+        'needs-retry',
+        limiter.on_receiving_response,
+    )
+    return limiter
+
+
+class ClientRateLimiter:
+    _MAX_RATE_ADJUST_SCALE = 2.0
+
+    def __init__(
+        self,
+        rate_adjustor,
+        rate_clocker,
+        token_bucket,
+        throttling_detector,
+        clock,
+    ):
+        self._rate_adjustor = rate_adjustor
+        self._rate_clocker = rate_clocker
+        self._token_bucket = token_bucket
+        self._throttling_detector = throttling_detector
+        self._clock = clock
+        self._enabled = False
+        self._lock = threading.Lock()
+
+    def on_sending_request(self, request, **kwargs):
+        if self._enabled:
+            self._token_bucket.acquire()
+
+    # Hooked up to needs-retry.
+    def on_receiving_response(self, **kwargs):
+        measured_rate = self._rate_clocker.record()
+        timestamp = self._clock.current_time()
+        with self._lock:
+            if not self._throttling_detector.is_throttling_error(**kwargs):
+                new_rate = self._rate_adjustor.success_received(timestamp)
+            else:
+                if not self._enabled:
+                    rate_to_use = measured_rate
+                else:
+                    rate_to_use = min(
+                        measured_rate, self._token_bucket.max_rate
+                    )
+                new_rate = self._rate_adjustor.error_received(
+                    rate_to_use, timestamp
+                )
+                logger.debug(
+                    "Throttling response received, new send rate: %s "
+                    "measured rate: %s, token bucket capacity "
+                    "available: %s",
+                    new_rate,
+                    measured_rate,
+                    self._token_bucket.available_capacity,
+                )
+                self._enabled = True
+            self._token_bucket.max_rate = min(
+                new_rate, self._MAX_RATE_ADJUST_SCALE * measured_rate
+            )
+
+
+class RateClocker:
+    """Tracks the rate at which a client is sending a request."""
+
+    _DEFAULT_SMOOTHING = 0.8
+    # Update the rate every _TIME_BUCKET_RANGE seconds.
+    _TIME_BUCKET_RANGE = 0.5
+
+    def __init__(
+        self,
+        clock,
+        smoothing=_DEFAULT_SMOOTHING,
+        time_bucket_range=_TIME_BUCKET_RANGE,
+    ):
+        self._clock = clock
+        self._measured_rate = 0
+        self._smoothing = smoothing
+        self._last_bucket = math.floor(self._clock.current_time())
+        self._time_bucket_scale = 1 / self._TIME_BUCKET_RANGE
+        self._count = 0
+        self._lock = threading.Lock()
+
+    def record(self, amount=1):
+        with self._lock:
+            t = self._clock.current_time()
+            bucket = (
+                math.floor(t * self._time_bucket_scale)
+                / self._time_bucket_scale
+            )
+            self._count += amount
+            if bucket > self._last_bucket:
+                current_rate = self._count / float(bucket - self._last_bucket)
+                self._measured_rate = (current_rate * self._smoothing) + (
+                    self._measured_rate * (1 - self._smoothing)
+                )
+                self._count = 0
+                self._last_bucket = bucket
+            return self._measured_rate
+
+    @property
+    def measured_rate(self):
+        return self._measured_rate